(i) Technical Field
A certain aspect of the embodiments discussed herein is related to an electronic circuit.
(ii) Related Art
Electronic circuits such as monolithic microwave integrated circuits (MMICs) are used in radio frequency (RE) or high frequency circuits, which handle RF signals such as filter circuits and impedance matching circuits. MMICs have a circuit pattern of a transmission line made of a metal such as gold (Au) formed on an insulation film on a semiconductor substrate and circuit elements formed thereon. Examples of the circuit elements included in MMICs are a field effect transistor (FET), a capacitor such as a metal-insulator-metal (MIM) capacitor, a resistor, a distributed-constant line, and an inductor.
The MIM capacitor is required to have improved reliability, and is proposed in, for example, Japanese Patent Application Publication No. 2003-110023.
If the MIM capacitor becomes defective, the MIM capacitor may fall in a short-circuited state in which a huge amount of current flows to a transmission line connected to the MIM capacitor and may fuse the transmission line. The position of fusing depends on various factors, which may include the shape of the transmission line and the fabrication process. When the transmission line is fused, a remainder of the transmission line may function as an open stub and may affect the characteristics of the electronic circuits greatly. A similar problem occurs in a case where a capacitor other than the MIM capacitor is used.